I have a DX58SO mother board and cannot install windows XP Pro.. During installation the keyboard stops working so I cannot answer install question. The mouse also does not work.Have updated BIOS, removed battery etc.I also have legacy USB enabled.What do you think I should try next?

There is no problem with the USB controllers on the board en you have tried all BIOS tweaks related to USB

There is not much more to do.

My dealer replaced the board and told me that the front USB ports may not be connected.

This was a wrong anwser, the fron USB ports where correct connected.

Intel should really fix this issue cause after contact with intel support , i've tried 3 different brand of keyboards and all have the same problem.

So, it's not a keyboard problem.

I could install XP Pro (32 bit) since I need XP for two applications that do'nt runn at all under a virtual XP session (virtualbox - Ubuntu 64)

This setup worked fine on my previos computer configuration (AMD 64 based) On this system, I had to remove the "press a key tot start windows install" from the XP boot CD and if I want to install ubuntu, then there too, I have to use some unattended setup to avaid that keyboard acion is needed at boot stage.

Look at the Nul mock led, the BIOS (if enabled) will turn this led on.

But ate then end of the boot stage (stage before 94) then the led turns off.

F2 and so work cause if you tap that key a few times during the splash screen, then the BIOS records the key sequence an will access

the BIOS or any other function key.

Now, cause windows XP is running: All USB ports work , no matter where I connect the keyboard and mouse, USB sticks, ALL usb ports work fine.

The only real difference is: windows uses drivers

So: Intel : it's sure not the keyboard problem.

So what's left? BIOS or Hardware ,

I could send this board back to the dealer (guarantee case) but they intend to replace the board for the thid time.

The big problem is: there are many users of this board (DX58SO smackover) that have no problem, but there are users with the keyboard problem.

Perhaps I should switch back to AMD and sure will if Intel is not fixing this.

Edit:

Check the board version and BIOS version: Downlaod the ID tool from Intel.